Older donor livers show early severe histological activity, fibrosis, and graft failure after liver transplantation for hepatitis C

An Overview of Liver Transplantation: Current Status, Recent Techniques, and Challenges-Perspectives From a Center in China

Liver transplantation is the best way to treat end-stage liver disease.With benefits from enhanced techniques, refined management, and advanced medications, liver transplant boasts a commendable 5-year survival rate for recipients. Nevertheless, acquiring the perioperative management and surgical skills essential for liver transplant is a time-consuming process for new surgeons. In addition, COVID-19 has also affected the field. Based on our actual situation in China, we have provided an overview of donor evaluation,recipient selection,transplant procedures, postoperative complications and management, longterm management, and pandemic strategies to guide new clinical surgeons in the field.

Impact of Donation After Circulatory Death Allografts on Outcomes After Liver Transplant for Hepatitis C: A Single-Center Experience and Review of the Literature

OBJECTIVES

We investigated the impact of liver transplant from donors after circulatory death on incidence and severity of recurrent hepatitis C virus infection, graft and patient survival and aimed to identify predictors of outcomes.

MATERIALS AND METHODS

We retrospectively reviewed all liver transplants performed at a single center (July 2007-February 2014). Patients with hepatitis C who underwent liver transplant from donors after circulatory death (group 1) were compared with hepatitis C patients who received grafts from donors after brain death (group 2) and patients without hepatitis C who received grafts from donors after circulatory death (group 3).We used the Kaplan-Meier method for survival analysis and performed a multivariable analysis for predictors of outcomes using Cox regression. Competing risk was used to analyze hepatitis C recurrence.

RESULTS

Of 196 patients, 107 were included: 25 in group 1, 46 in group 2, and 36 in group 3. All 3 groups were comparable, except for longer cold ischemia time (P < .01) in group 1, lower Model for End-Stage Liver Disease score at transplant in groups 1 and 3 (P < .01), and greater proportion of recipients with hepatocellular carcinoma in groups 1 and 2 (P = .02). Hepatitis C recurrence and severe recurrence at 1 and 3 years were higher in group 1 (but not statistically significant). Severe recurrence was noted in 17% versus 8% at 1 year (P = .12) and 30% versus 14% at 3 years (P = .08). Graft and patient survival rates at 1, 3, and 5 years were comparable in all 3 study groups.

CONCLUSIONS

Recurrent hepatitis C, including severe recurrence, was greater following donation after circulatory death compared with donation after brain death liver transplant. However, graft survival and patient survival were comparable, including in recipients of donation after circulatory death grafts without hepatitis C.

Liver donor age affects hepatocyte function through age-dependent changes in decellularized liver matrix

The only treatment available for end stage liver diseases is orthotopic liver transplantation. Although there is a big donor scarcity, many donor livers are discarded as they do not qualify for transplantation. Alternatively, decellularization of discarded livers can potentially render them transplantable upon recellularization and functional testing. The success of this approach will heavily depend on the quality of decellularized scaffolds which might show variability due to factors including age. Here we assessed the age-dependent differences in liver extracellular matrix (ECM) using rat and human livers. We show that the liver matrix has higher collagen and glycosaminoglycan content and a lower growth factor content with age. Importantly, these changes lead to deterioration in primary hepatocyte function potentially due to ECM stiffening and integrin-dependent signal transduction. Overall, we show that ECM changes with age and these changes significantly affect cell function thus donor age should be considered as an important factor for bioengineering liver substitutes.

Biliary Complication in Pediatric Liver Transplantation: a Single-Center 15-Year Experience

BACKGROUND

The incidence and several risk factors of biliary complication (BC) following pediatric liver transplantation (LT) are widely known, but data on long-term outcomes and management is limited. This retrospective study aimed to investigate the incidence, associated risk factors, management, and outcomes of early and late BC in pediatric LT.

METHODS

This study enrolled 134 pediatric patients (< 18 years old) who underwent LT at a tertiary care center in Taiwan between January 2001 and December 2015. Diagnosis of BC was based on clinical, biochemical, and radiologic examinations. Clinical data and chart records were reviewed and compared between the groups.

RESULTS

Among the 134 children, 21 children (15.7%) had BC after LT. Nine children had early complications, including leakage plus stricture (n = 2), stricture only (n = 2), and leakage only (n = 5). Twelve children had late BC; all of whom had anastomotic stricture. Of the 21 patients with BC, 11 patients (52.4%) were treated without surgery. The median time of first treatment for BC was 6.5 months (range, 11 days to 6.2 years). Five of the 9 patients with early complications and two of the 12 patients with late complications died of biliary tract infection. The major risk factors of BC in pediatric LT were (1) recipient age > 2 years, (2) Kasai portoenterostomy revision, and (3) hepatic artery thrombosis.

CONCLUSIONS

Several risk factors of BC in pediatric LT were identified. Children with early BC appeared to have relatively unfavorable outcomes. However, late BC treated by either radiological or surgical methods appeared to have a relatively good long-term prognosis.

Liver graft preservation methods during cold ischemia phase and normothermic machine perfusion

The growing demand for donor organs requires measures to expand donor pool. Those include extended criteria donors, such as elderly people, steatotic livers, donation after cardiac death, etc. Static cold storage to reduce metabolic requirements developed by Collins in late 1960s is the mainstay and the golden standard for donated organ protection. Hypothermic machine perfusion provides dynamic organ preservation at 4°C with protracted infusion of metabolic substrates to the graft during the ex vivo period. It has been used instead of static cold storage or after it as short perfusion in transplant center. Normothermic machine perfusion (NMP) delivers oxygen, and nutrition at physiological temperature mimicking regular environment in order to support cellular function. This would minimize effects of ischemia/reperfusion injury. Potentially, NMP may help to estimate graft functionality before implantation into a recipient. Clinical studies demonstrated at least its non-inferiority or better outcomes vs static cold storage. Regular grafts donated after brain death could be safely preserved with convenient static cold storage. Except for prolonged ischemia time where hypothermic machine perfusion started in transplant center could be estimated to provide possible positive reconditioning effect. Use of hypothermic machine perfusion in regular donation instead of static cold storage or in extended criteria donors requires further investigation. Multicenter randomized clinical trial supposed to be completed in December 2021. Extended criteria donors need additional measures for graft storage and assessment until its implantation. NMP is actively evaluating promising method for this purpose. Future studies are necessary for precise estimation and confirmation to issue clinical practice recommendations.

Liver Transplantation With Old Grafts: A Ten-Year Experience

BACKGROUND

The persistent scarcity of donors has prompted liver transplantation teams to find solutions for increasing graft availability. We report our experience of liver transplantations performed with grafts from older donors, specifically over 70 and 80 years old.

PATIENTS AND METHODS

We analyzed our prospectively maintained single-center database from January 1, 2005, to December 31, 2014, with 380 liver transplantations performed in 354 patients. Six groups were composed according to donor age: <40 (n = 84), 40 to 49 (n = 67), from 50 to 59 (n = 62), from 60 to 69 (n = 76), from 70 to 79 (n = 64), and ≥80 years (n = 27).

RESULTS

Donors <40 years of age had a lower body mass index, died more often from trauma, and more often had cardiac arrest and high transaminase levels. In contrast, older donors (≥70 years of age) died more often from stroke. Recipients of grafts from donors <50 years of age were more frequently infected by hepatitis C virus; recipients of oldest grafts more often had hepatocellular carcinoma. Cold ischemia time was the shortest in donors >80 years of age. Patient survival was not significantly different between the groups. In multivariate analysis, factors predicting graft loss were transaminase peak, retransplantation and cold ischemia time but not donor age.

CONCLUSIONS

Older donors >70 and >80 years of age could provide excellent liver grafts.

The Role of Normothermic Perfusion in Liver Transplantation (TRaNsIT Study): A Systematic Review of Preliminary Studies

INTRODUCTION

The success of liver transplantation has been limited by the unavailability of suitable donor livers. The current organ preservation technique, i.e., static cold storage (SCS), is not suitable for marginal organs. Alternatively, normothermic machine perfusion (NMP) promises to recreate the physiological environment and hence holds promise for the better organ preservation. The objective of this systematic review is to provide an overview of the safety, benefits, and insight into the other potential useful parameters of NMP in the liver preservation.

MATERIAL AND METHODS

We searched the current literature following registration in the International Prospective Register of Systematic Reviews (PROSPERO) with registration number CRD42018086034 for prospective trials comparing the role of NMP device to SCS in liver transplant by searching the PubMed, EMBASE, Cochrane, BIOSIS, Crossref, and Scopus databases and clinical trial registry.

RESULTS

The literature search identified five prospective clinical trials (four being early phase single institutional and single randomized multi-institutional) comparing 187 donor livers on NMP device to 273 donor livers on SCS. The primary outcome of interest was to assess the safety and graft survival at day 30 after transplant following NMP of the donor liver. Secondary outcomes included were early allograft dysfunction (EAD) in the first seven days; serum measures of liver functions as bilirubin, aspartate aminotransferase (AST), alanine amino transferase (ALT), alkaline phosphatase (ALP), and international normalized ratio (INR) on days 1-7; major complications as defined by a Clavien-Dindo score ≥ 3; and patient and graft survival and biliary complications at six months. The peaked median AST level between days 1 and 7 in the five trials was 417-1252 U/L (range 84-15009 U/L) while on NMP and 839-1474 U/L (range 153-8786 U/L) in SCS group. The median bilirubin level on day 7 ranged within 25-79 µmol/L (range 8-344 µmol/l) and 30-47.53 µmol/l (range 9-340 µmol/l) in NMP and SCS groups, respectively. A single case of PNF was reported in NMP group in the randomized trial while none of the other preliminary studies reported any in either group. There was intertrial variability in EAD which ranged within 15-56% in NMP group while being within 23-37% in SCS group. Biliary complications observed in NMP group ranged from 0 to 20%. Single device malfunction was reported in randomized controlled trial leading to renouncement of transplant while none of the other trials reported any machine failure, although two user related device errors inadvertent were reported.

CONCLUSION

This review outlines that NMP not only demonstrated safety and efficacy but also provided the favourable environment of organ preservation, repair, and viability assessment to donor liver prior to the transplantation with low rate of posttransplantation complication as PNF, EAD, and biliary complication; however further studies are needed to broaden our horizon.

Frozen Sections of the Liver

Intraoperative consultation requires skills in gross examination and histologic diagnosis, as well as an ability to perform rapid interpretations under time constraints. The aim of this review is to provide surgical pathologists with a framework for dealing with hepatic specimens in the frozen section area by covering common clinical scenarios and histologic findings. Differential diagnoses are considered in relation to primary hepatic neoplasia and metastatic diseases. Benign mimics of malignancy and other pitfalls in frozen section diagnosis of lesional tissue are covered. Finally, assessment of donor liver biopsy for organ transplant evaluation is discussed.

Right lobe living donors ages 55 years old and older in liver transplantation

The evidence is insufficient for safe use of elderly donors in adult-to-adult living donor liver transplantation (LDLT). The aim of this study was to evaluate the outcomes of right lobe LDLT by donor age (≥55 versus < 55 years). All living donors who underwent right hepatectomy at the authors' institution between March 2008 and December 2015 were divided into 2 groups: group A with an age ≥ 55 years and group B with an age of <55 years. The selection criteria for elderly donor were preservation of middle hepatic vein, remnant liver volume ≥30%, and no or mild fatty liver. The matching criteria of recipients for the elderly donor grafts were Model for End-Stage Liver Disease score of <25, graft-to-recipient weight ratio of >0.8%, and body mass index of <25 kg/m² . Perioperative data, complications by the Clavien classification, and the outcomes with at least 12 months follow-up were compared. A total of 42 donors were enrolled in group A and 498 in group B. No significant differences in operative parameters were observed between the 2 groups. The peak postoperative aspartate aminotransferase, alanine aminotransferase, and total bilirubin levels made no difference between the 2 groups. The peak international normalized ratio level was significantly lower in group A than in group B (P = 0.001). All donors recovered completely with no significant differences in overall complications between the 2 groups. All recipients of grafts from donors in group A showed good initial function with no significant differences in 1-year graft and patient survival or biliary complications between 2 groups. These results provide clinical evidence for feasibility of right hepatectomy in living donors aged ≥ 55 years without compromising donor safety or recipient outcomes. Liver Transplantation 23 1305-1311 2017 AASLD.

The Current State of Liver Transplantation in the United States: Perspective From American Society of Transplant Surgeons (ASTS) Scientific Studies Committee and Endorsed by ASTS Council

This article is a review of the salient points and a future prospective based on the 2014 Organ Procurement and Transplantation Network (OPTN)/Scientific Registry of Transplant Recipients (SRTR) liver donation and transplantation data report recently published by the American Journal of Transplantation. Emphasis of our commentary and interpretation is placed on data relating to waitlist dynamics, organ utilization rates, the impact of recent advances in the treatment of hepatitis C, and the increases in end-stage renal disease among liver transplant candidates. Finally, we share our vision on potential areas of innovation that are likely to significantly improve the field of liver transplantation in the near future.

Hepatitis C in Liver Allograft Recipients: Utility of One-Year Post-Transplantation Biopsy as an Indicator of Antiviral Therapy

Background

All-oral interferon-free regimens for hepatitis C viral (HCV) infection are highly efficacious; however, high cost is a barrier to applicability. Liver allograft recipients are particularly likely to benefit from therapy as HCV often leads to graft dysfunction and loss. In this study, we aimed to establish the utility of allograft biopsy at 1 year post-transplant as an indicator of treatment.

Methods and Results

Among 252 liver recipients enrolled, 136 (54%) developed severe disease (fibrosing cholestatic hepatitis (FCH) or fibrosis stage ≥ 2 at 1 year post-transplant). Multivariable analysis revealed younger recipient age and female gender, older donor age and T cell depletive therapy to be independent predictors of severe disease. Recipients with severe disease had higher rate of further graft loss compared to those with mild disease. Patients with mild disease and sustained virologic response (SVR) had the best survival rate, whereas those with severe disease and viremia had the worst survival (96% versus 63% at 5 years).

Conclusion

In conclusion, allograft biopsy at 1 year helps identify recipients at high risk of further graft dysfunction and loss. In view of high cost of therapy, treatment should be preferably directed to high-risk patients including those with FCH or fibrosis stage ≥ 2 by 1 year post-transplant.

Donor Factors Including Donor Risk Index Predict Fibrosis Progression, Allograft Loss, and Patient Survival following Liver Transplantation for Hepatitis C Virus

BACKGROUND

The utilization of liver transplantation (LT) is limited by the availability of suitable organs. This study aimed to assess the impact of the donor risk index (DRI) and other donor characteristics on fibrosis progression, graft, and patient survival in hepatitis C virus (HCV)-infected LT recipients.

METHODS

HCV-infected LT recipients who had at least 2 post-LT protocol liver biopsy specimens available were included. Hazard ratio for bivariate analysis was computed using Cox proportional hazard regression analysis.

RESULTS

Of 312 recipients, 26.6% died over a median follow-up of 58.5 months (95% CI: 46.5-67.3). Fourteen patients underwent re-transplantation. Mean time to graft failure was 84.3 months, median follow-up: 59 months, 95% CI (48.2, 68.3). DRI >1.5 was significantly associated with patient and graft survival (P = 0.04). Of the subset of 104 individuals who underwent histological analysis, 67.3% progressed to ≥F2. On multivariate analysis, significant donor-specific predictors of fibrosis progression were: donor age >50 years and DRI >1.7.

CONCLUSIONS

(1) Fibrosis progression in HCV-infected LT recipients is strongly associated with donor characteristics, specifically donor age and DRI. (2) DRI, an objective measure of donor quality, appears to correlate both with rate of histological progression and overall patient/graft survival.

Liver transplant recipients and prioritization of anti-HCV therapy: an Italian cohort analysis

BACKGROUND AND AIMS

In patients with hepatitis C virus (HCV), recurrence of infection after liver transplant (LT) is universal and associated with worst survival. We present the results of an Italian cohort to compare the 3-year outcome of HCV-Ab-positive and HCV-Ab-negative LT recipients and to assess the potential interaction between HCV-Ab sero-status and other risk factors for LT failure.

METHODS

The study is a multicentre cohort including a sample of liver transplant centres. Participant's information was collected at the local level. The best functional form of variables was decided according to the objective methods based on information theory. Association between transplant failure and potential risk factors was assessed in univariate and multivariate Poisson regression model with random intercept.

RESULTS

Between June 2007 and May 2009, 1164 LT recipients were enrolled in 16 Italian transplant centres, of them 275 (23.63%) experienced LT failure. Incidence rates of LT failure was 0.32 and 0.23 per 1000 person-days in HCV-Ab-positive and HCV-Ab-negative recipients respectively (P = 0.003). Inferential models according to Akaike information criterion indicated that donor-recipient age difference and donor-recipient sex matching were more informative to predict LT failure than the age and the sex as separate variables. Multivariate analysis provided evidence that HCV-Ab sero-status, time after LT, donor-recipient age difference, donor-recipient sex matching and recipient's MELD score were significantly associated with LT failure. Moreover, the effect of HCV-Ab sero-status on LT failure was modified by the simultaneous action of time after LT and donor-recipient age difference. No interaction was found between recipient's HCV-Ab sero-status and either recipient's MELD or donor-recipient sex matching.

CONCLUSION

In view of the imminent introduction of new anti-HCV therapies, our study provides information to assess which LT recipients should be prioritized for receiving these highly effective, but expensive, new treatments. This is particularly relevant for those clinical settings where healthcare prioritization is endorsed by national authorities.

Effect of Blood Donor Characteristics on Transfusion Outcomes: A Systematic Review and Meta-Analysis

Optimal selection of blood donors is critical for ensuring the safety of blood products. The current selection process is concerned principally with the safety of the blood donor at the time of donation and of the recipient at the time of transfusion. Recent evidence suggests that the characteristics of the donor may affect short- and long-term transfusion outcomes for the transfused recipient. We conducted a systematic review with the primary objective of assessing the association between blood donor characteristics and red blood cell (RBC) transfusion outcomes. We searched MEDLINE, EMBASE, and Cochrane Central databases and performed manual searches of top transfusion journals for all available prospective and retrospective studies. We described study characteristics, methodological quality, and risk of bias and provided study-level effect estimates and, when appropriate, pooled estimates with 95% confidence intervals using the Mantel-Haenszel or inverse variance approach. The overall quality of the evidence was graded using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. From 6121 citations identified by our literature search, 59 studies met our eligibility criteria (50 observational, 9 interventional). We identified the evaluation of association of 17 donor characteristics on RBC transfusion outcome. The risk of bias and confounding of the included studies was high. The quality of evidence was graded as very low to low for all 17 donor characteristics. Potential associations were observed for donor sex with reduced survival at 90 days and 6 months in male recipients that receive donated blood from females (hazard ratio 2.60 [1.09, 6.20] and hazard ratio 2.40 [1.10, 5.24], respectively; n = 1), Human Leukocyte Antigen - antigen D Related (HLA-DR) selected transfusions (odds ratio [OR] 0.39 [0.15, 0.99] for the risk of transplant alloimmunization, n = 9), presence of antileukocyte antibodies (OR 5.84 [1.66, 20.59] for risk of transfusion-related acute lung injury, n = 4), and donor RBC antigens selection (OR 0.20 [0.08, 0.52] for risk of alloimmunization, n = 4). Based on poor quality evidence, positive antileukocyte antibodies, female donor to male recipients, HLA-DR selected RBC transfusion, or donor RBC antigen selection may affect RBC transfusion outcome. Our findings that donor characteristics may be associated with transfusion outcomes warrant establishing vein-to-vein data infrastructure to allow for large robust evaluations. PROSPERO registration number: CRD42013006726.

Management of liver transplantation waiting list for decompensated cirrhosis in a Spanish tertiary hospital: differences between hepatitis C virus recipients and other etiologies

BACKGROUND

Decompensated cirrhosis due to hepatitis C virus (HCV) is one of the main indications for liver transplantation (LT) in Spain. Recurrence of HCV after LT is the main cause of graft loss and death in HCV-positive recipients. Advanced donor age determines a more aggressive recurrence of HCV and a shorter survival. In this setting, in our liver unit, grafts from younger donors are allocated to HCV-positive recipients. The aim of this study was a comparative analysis of allocation of grafts in HCV-positive recipients versus other etiologies and the impact on waiting list time, Model for End-Stage Liver Disease (MELD) score progression until LT, need of admission in a hospital, survival until LT.

METHODS

This was a retrospective study from the cohort of patients included in the waiting list for LT owing to decompensated cirrhosis in the Hospital Gregorio Marañón from January 2008 to June 2013.

RESULTS

A total of 91 patients were included; 63 patients (69.23%) received LT; 19 (20.88%) retired from the waiting list: 6 because of improvement, 11 (12.08%) because of death. In both groups, the age of recipients was similar (HCV 52 y vs other 53 y; P = .549). HCV patients were included in the waiting list with lower MELD score than other etiologies (HCV 16.1 vs other 19.4; P = .010); nevertheless, MELD score was similar at the time of LT in both groups (HCV 18.9 vs other 19.4; P = .675). Time on waiting list was significantly longer in HCV patients (198 d vs 86 d; P = .002) and they were admitted in hospital more days (30 d vs 12 d; P = .03). Donor age in the HCV group was significantly lower (64.3 y vs 54.7 y; P = .006). The intention-to-treat survival analysis did not show differences between the groups (log rank = 0.504).

CONCLUSIONS

HCV patients with decompensated cirrhosis receive grafts from younger donors. HCV patients remain waiting longer for an optimal organ and suffer MELD deterioration and more days admitted in hospital. These differences in allocation of grafts did not affect final survival. In our experience, designating younger organs to HCV-positive patients does not penalize neither HCV recipients nor recipients with other etiologies.

The corrected donor age for hepatitis C virus-infected liver transplant recipients

Donor age has become the dominant donor factor used to predict graft failure (GF) after liver transplantation (LT) in hepatitis C virus (HCV) recipients. The purpose of this study was to develop and validate a model of corrected donor age (CDA) for HCV LT recipients that transforms the risk of other donor factors into the scale of donor age. We analyzed all first LT recipients with HCV in the United Network for Organ Sharing (UNOS) registry from January 1998 to December 2007 (development cohort, n = 14,538) and January 2008 to December 2011 (validation cohort, n = 7502) using Cox regression, excluding early GF (<90 days from LT). Accuracy in predicting 1 year GF (death or repeat LT) was assessed with the net reclassification index (NRI). In the development cohort, after controlling for pre-LT recipient factors and geotemporal trends (UNOS region, LT year), the following donor factors were independent predictors of GF, all P < 0.05: donor age (hazard ratio [HR], 1.02/year), donation after cardiac death (DCD; HR, 1.31), diabetes (HR, 1.23), height < 160 cm (HR, 1.13), aspartate aminotransferase (AST) ≥ 120 U/L (HR, 1.10), female (HR, 0.94), cold ischemia time (CIT; HR, 1.02/hour), and non-African American (non-AA) donor-African American (AA) recipient (HR, 1.65). Transforming these risk factors into the donor age scale yielded the following: DCD = +16 years; diabetes = +12 years; height < 160 cm = +7 years; AST ≥ 120 U/L = +5 years; female = -4 years; and CIT = +1 year/hour > 8 hours and -1 year/hour < 8 hours. There was a large effect of donor-recipient race combinations: +29 years for non-AA donor and an AA recipient but only +5 years for an AA donor and an AA recipient, and -2 years for an AA donor and a non-AA recipient. In a validation cohort, CDA better classified risk of 1-year GF versus actual age (NRI, 4.9%; P = 0.009) and versus the donor risk index (9.0%, P < 0.001). The CDA, compared to actual donor age, provides an intuitive and superior estimation of graft quality for HCV-positive LT recipients because it incorporates additional factors that impact LT GF rates.

Projections in donor organs available for liver transplantation in the United States: 2014-2025

With the aging US population, demographic shifts, and obesity epidemic, there is potential for further exacerbation of the current liver donor shortage. We aimed to project the availability of liver grafts in the United States. We performed a secondary analysis of the Organ Procurement and Transplantation Network database of all adult donors from 2000 to 2012 and calculated the total number of donors available and transplanted donor livers stratified by age, race, and body mass index (BMI) group per year. We used National Health and Nutrition Examination Survey and Centers for Disease Control and Prevention historical data to stratify the general population by age, sex, race, and BMI. We then used US population age and race projections provided by the US Census Bureau and the Weldon Cooper Center for Public Service and made national and regional projections of available donors and donor liver utilization from 2014 to 2025. We performed sensitivity analyses and varied the rate of the rise in obesity, proportion of Hispanics, population growth, liver utilization rate, and donation after cardiac death (DCD) utilization. The projected adult population growth in the United States from 2014 to 2025 will be 7.1%. However, we project that there will be a 6.1% increase in the number of used liver grafts. There is marked regional heterogeneity in liver donor growth. Projections were significantly affected by changes in BMI, DCD utilization, and liver utilization rates but not by changes in the Hispanic proportion of the US population or changes in the overall population growth. Overall population growth will outpace the growth of available donor organs and thus potentially exacerbate the existing liver graft shortage. The projected growth in organs is highly heterogeneous across different United Network for Organ Sharing regions. Focused strategies to increase the liver donor pool are warranted.

Impact of elderly donors for liver transplantation: A single-center experience

Elderly donor grafts for liver transplantation (LT) are recognized to be marginal grafts. The present study investigated the impact of using elderly donors for LT. Between June 1990 and August 2012, 1631 patients received LT at Kyoto University Hospital. Out of 1631 patients, 1597 patients received living donor liver transplantation (LDLT), whereas the other 34 patients underwent deceased donor liver transplantation (DDLT). Seventy-five grafts that were used came from individuals who were ≥60 years old. We retrospectively analyzed the recipients' survival rates according to donor age. The overall survival rates of the recipients of all LDLT (P < 0.001), adult-to-adult LDLT (P = 0.007), all DDLT (P = 0.026), and adult-to-adult DDLT (P = 0.011) were significantly lower for the elderly donor group versus the younger group and especially for those who were hepatitis C-positive. A multivariate analysis revealed that donor age, ABO incompatibility, and preoperative intensive care unit stay were independent risk factors for poor patient survival in adult-to-adult LDLT. However, no significant differences existed between the 2 groups among those who received adult-to-adult LDLT in and after April 2006. No significant association was found between donor age and incidence of acute cellular rejection. In conclusion, donor age was closely related to the survival rate for LDLT and DDLT, although the impact of donor age was not shown in the recent cases.

Hepatitis C virus recurrence after liver transplantation: A 10-year evaluation

AIM: To evaluate the predictors of 10-year survival of patients with hepatitis C recurrence.

METHODS: Data from 358 patients transplanted between 1989 and 2010 in two Italian transplant centers and with evidence of hepatitis C recurrence were analyzed. A χ², Fisher’s exact test and Kruskal Wallis’ test were used for categorical and continuous variables, respectively. Survival analysis was performed at 10 years after transplant using the Kaplan-Meier method, and a log-rank test was used to compare groups. A P level less than 0.05 was considered significant for all tests. Multivariate analysis of the predictive role of different variables on 10-year survival was performed by a stepwise Cox logistic regression.

RESULTS: The ten-year survival of the entire population was 61.2%. Five groups of patients were identified according to the virological response or lack of a response to antiviral treatment and, among those who were not treated, according to the clinical status (mild hepatitis C recurrence, “too sick to be treated” and patients with comorbidities contraindicating the treatment). While the 10-year survival of treated and untreated patients was not different (59.1% vs 64.7%, P = 0.192), patients with a sustained virological response had a higher 10-year survival rate than both the “non-responders” (84.7% vs 39.8%, P < 0.0001) and too sick to be treated (84.7% vs 0%, P < 0.0001). Sustained virological responders had a survival rate comparable to patients untreated with mild recurrence (84.7% vs 89.3%). A sustained virological response and young donor age were independent predictors of 10-year survival.

CONCLUSION: Sustained virological response significantly increased long-term survival. Awaiting the interferon-free regimen global availability, antiviral treatment might be questionable in selected subjects with mild hepatitis C recurrence.

Serum aspartate aminotransferase levels and previous histopathological findings enable reduction of protocol liver biopsies after liver transplantation for hepatitis C

BACKGROUND

Hepatitis C virus (HCV) infection remains the leading indication for liver transplantation (LT) worldwide. Recurrent hepatitis C following LT is universal, and significant fibrosis (SF, Metavir fibrosis stage ≥2) apparent on protocol biopsy typically prompts antiviral therapy.

OBJECTIVE

To determine the optimal timing of protocol liver biopsies in this setting.

METHODS

A total of 151 patients who underwent LT related to HCV infection between July 2004 and December 2009 were analyzed retrospectively. Data regarding protocol liver biopsies at six, 12 and 24 months post-LT, conventional laboratory parameters and demographic information were obtained.

RESULTS

The 151 patients included in the present study had significantly lower serum aspartate aminotransferase (AST) levels than the four patients who progressed to receive antiviral treatment for SF before six months post-LT (P<0.001). AST level, but not alanine aminotransferase level, histological activity or fibrosis stage at the six-month biopsy was independently associated with the progression to SF at 12 months (P<0.05). However, AST level, histological activity and fibrosis stage at the 12-month biopsy emerged as independent parameters associated with progression to SF at 24 months (P<0.05).

CONCLUSION

The protocol liver biopsy at six months could be eliminated, especially in patients who consistently exhibit low AST levels. Histological activity, the presence or absence of fibrosis, and AST values at the 12-month biopsy may lead to the decision to defer the protocol biopsy at 24 months or result in earlier introduction of antiviral therapy.

Risk factors for early and late biliary complications in pediatric liver transplantation

BC are a common source of morbidity after pediatric LT. Knowledge about risk factors may help to reduce their incidence. Retrospective analysis of BC in 116 pediatric patients (123 LT) (single institution, 05/1990-12/2011, medium follow-up 7.9 yr). One-, five-, and 10-yr survival was 91.1%, no patient died of BC. Prevalence and risk factors for anastomotic and intrahepatic BC were examined. There were 29 BC in 123 LT (23.6%), with three main categories: 10 (8.1%) primary anastomotic strictures, eight (6.5%) anastomotic leaks, and three (2.4%) intrahepatic strictures. Significant risk factors for anastomotic leaks were total operation time (increase 1.26-fold) and early HAT (<30 days post-LT; increase 5.87-fold). Risk factor for primary anastomotic stricture was duct-to-duct choledochal anastomosis (increase 5.96-fold when compared to biliary-enteric anastomosis). Risk factors for intrahepatic strictures were donor age >48 yr (increase 1.09-fold) and MELD score >30 (increase 1.2-fold). To avoid morbidity from anastomotic BC in pediatric LT, the preferred biliary anastomosis appears to be biliary-enteric. Operation time should be kept to a minimum, and HAT must by all means be prevented. Children with a high MELD score or receiving livers from older donors are at increased risk for intrahepatic strictures.

Recurrent HCV after liver transplantation-mechanisms, assessment and therapy

Chronic HCV infection is the leading indication for liver transplantation. However, as a result of HCV recurrence, patient and graft survival after liver transplantation are inferior compared with other indications for transplantation. HCV recurrence after liver transplantation is associated with considerable mortality and morbidity. The development of HCV-related fibrosis is accelerated after liver transplantation, which is influenced by a combination of factors related to the virus, donor, recipient, surgery and immunosuppression. Successful antiviral therapy is the only treatment that can attenuate fibrosis. The advent of direct-acting antiviral agents (DAAs) has changed the therapeutic landscape for the treatment of patients with HCV. DAAs have improved tolerability, and can potentially be used without PEG-IFN for a shorter time than previous therapies, which should result in better outcomes. In this Review, we describe the important risk factors that influence HCV recurrence after liver transplantation, highlighting the mechanisms of fibrosis and the integral role of hepatic stellate cells. Indirect and direct assessment of fibrosis, in addition to new antiviral therapies, are also discussed.

Restricting liver transplant recipients to younger donors does not increase the wait-list time or the dropout rate: the hepatitis C experience

Older donor age is associated with lower graft and patient survival among all recipients of liver transplantation (LT). Among patients with hepatitis C virus (HCV), donor age is one of the strongest predictors of fibrosis severity and graft loss. We evaluated the implementation of a donor age restriction policy for LT patients with HCV at a single center and the effects that this policy had on wait-list (WL) and post-LT outcomes for HCV and non-HCV patients. This was a cohort study of 2388 WL patients and 1015 LT recipients between March 2002 and January 2013 and reflected 3 different eras of donor age policies. With the donor age restriction, the median donor age was reduced in LT recipients with HCV versus LT recipients without HCV (30 versus 48 years, P < 0.001) without differences in the WL time (10.6 versus 8.0 months, P = 0.23). According to a competing risks regression, those with HCV and those without HCV had lower subhazard ratios (SHRs) of dropout or death on the WL during the donor age restriction era versus the era without donor age restriction [SHR = 0.68 (P < 0.01) and SHR = 0.64 (P = 0.01), respectively]. No differences were seen in early post-LT survival for patients with or without HCV between eras (P = 0.7 and P = 0.88, respectively). In conclusion, we show that donor age restriction for HCV results in a lower donor age for HCV recipients without obvious adverse WL consequences. Although additional studies are needed, our results demonstrate the feasibility of donor age restriction for LT recipients with HCV, and such information may be relevant to programs with limited access to new antiviral therapies for which modifying the risk of severe disease remains of paramount importance.

Post-liver transplant hepatitis C virus recurrence: an unresolved thorny problem

Hepatitis C virus (HCV)-related cirrhosis represents the leading cause of liver transplantation in developed, Western and Eastern countries. Unfortunately, liver transplantation does not cure recipient HCV infection: reinfection universally occurs and disease progression is faster after liver transplant. In this review we focus on what happens throughout the peri-transplant phase and in the first 6-12 mo after transplantation: during this crucial period a completely new balance between HCV, liver graft, the recipient's immune response and anti-rejection therapy is achieved that will deeply affect subsequent outcomes. Nearly all patients show an early graft reinfection, with HCV viremia reaching and exceeding pre-transplant levels; in this setting, histological assessment is essential to differentiate recurrent hepatitis C from acute or chronic rejection; however, differentiating the two patterns remains difficult. The host immune response (mainly cellular mediated) appears to be crucial both in the control of HCV infection and in the genesis of rejection, and it is also strongly influenced by immunosuppressive treatment. At present no clear immunosuppressive strategy could be strongly recommended in HCV-positive recipients to prevent HCV recurrence, even immunotherapy appears to be ineffective. Nonetheless it seems reasonable that episodes of rejection and over-immunosuppression are more likely to enhance the risk of HCV recurrence through immunological mechanisms. Both complete prevention of rejection and optimization of immunosuppression should represent the main goals towards reducing the rate of graft HCV reinfection. In conclusion, post-transplant HCV recurrence remains an unresolved, thorny problem because many factors remain obscure and need to be better determined.

Role of toll-like receptors in liver transplantation

Toll-like receptors (TLRs) are pathogen recognition receptors that orchestrate the innate immune response and the subsequent adaptive immune response. TLRs can be triggered by exogenous ligands expressed by invading pathogens or by the release of endogenous ligands, such as that occurring through cellular injury during the transplantation process. They are now recognized to play an important role in many facets of transplantation biology, including rejection and tolerance, ischemia/reperfusion injury (IRI), and infections after transplantation. The role of TLRs in liver transplantation is unique with respect to other organ transplants because the portal circulation is a continuous source of TLR2 and TLR4 ligands, and this influences TLR signaling pathways, which have a central role in transplantation immunity. This review provides a critical update on recent data outlining the important role of TLRs in liver transplantation, and there is a particular focus on emerging advances in our understanding of rejection and tolerance, IRI, and infections after transplantation and on the ways in which these events may influence the recurrence of diseases such as hepatitis C infection after liver transplantation.

Predictors of disease recurrence post living donor liver transplantation in end stage chronic HCV patients

HCV recurrence represents a universal phenomenon after liver transplantation. In this study Fifty HCV patients who underwent living donor liver transplantation were enrolled and factors that may accelerate HCV reinfection of the allograft such as donor's age and degree of liver steatosis, recipient's age, gender, BMI, MELD score, liver functions, HCV viral load, type of immunosuppressive drug, and genetic polymorphisms of IL28B, OAS, and IL1B were studied. The results of disease-free survival (DFS) rates showed inverse correlation with the recipient's postoperative levels of ALT, AST, ALP (P < 0.001, <0.001, and 0.006 resp.) as well as pre- and postoperative titers of HCV RNA (P < 0.003 and <0.001 resp.). Recipient's IL28B SNP was a significant factor in predicting postoperative DFS (P < 0.025). However, SNPs in OAS and IL1B genes had no apparent correlation with DFS. Cox proportional hazards model revealed that patients with elevated levels of ALT, preoperative viral titers, IL28B CT, and IL28B TT were 8.28, 4.22, 3.35, and 1.36 times, respectively, more likely to develop recurrence. In conclusion IL28B SNP, ALT level, and preoperative HCV titer besides proper choice of immunosuppressant are helpful for predicting posttransplant HCV recurrence and DFS.

Hepatitis C recurrence: the Achilles heel of liver transplantation

Hepatitis C virus (HCV) infection is the most common indication for liver transplantation worldwide; however, recurrence post transplant is almost universal and follows an accelerated course. Around 30% of patients develop aggressive HCV recurrence, leading to rapid fibrosis progression (RFP) and culminating in liver failure and either death or retransplantation. Despite many advances in our knowledge of clinical risks for HCV RFP, we are still unable to accurately predict those most at risk of adverse outcomes, and no clear consensus exists on the best approach to management. This review presents a critical overview of clinical factors shown to influence the course of HCV recurrence post transplant, with particular focus on recent data identifying the important role of metabolic factors, such as insulin resistance, in HCV recurrence. Emerging data for genetic markers of HCV recurrence and their usefulness for predicting adverse outcomes will also be explored.

Matching donor to recipient in liver transplantation: Relevance in clinical practice

Achieving optimum outcomes after liver transplantation requires an understanding of the interaction between donor, graft and recipient factors. Within the cohort of patients waiting for a transplant, better matching of the donor organ to the recipient will improve transplant outcomes and benefit the overall waiting list by minimizing graft failure and need for re-transplantation. A PubMed search was conducted to identify published literature investigating the effects of donor factors such as age, gender, ethnicity, viral serology; graft factors such as size and quality, recipient factors such as age, size, gender and transplant factors such as major or minor blood group incompatibility and immunological factors. We also report technical and therapeutic modifications that can be used to manage donor-recipient mismatch identified from literature and the authors’ clinical experience. Multiple donor and recipient factors impact graft survival after liver transplantation. Appropriate matching based on donor-organ-recipient variables, modification of surgical technique and innovative peri-transplant strategies can increase the donor pool by utilizing grafts from marginal donors that are traditionally turned down.

Identifying the superior measure of rapid fibrosis for predicting premature cirrhosis after liver transplantation for hepatitis C

BACKGROUND

Hepatitis C virus (HCV) recurrence post liver transplant is universal, with a subgroup of patients developing rapid hepatic fibrosis. Various clinical definitions of rapid fibrosis (RF) have been used to identify risks for rapid progression, but their comparability and efficacy at predicting adverse outcomes has not been determined.

METHODS

Retrospective data analysis was conducted on 100 adult patients with HCV who underwent liver transplantation at a single center. We measured year 1 fibrosis progression (RF defined as METAVIR F score ≥ 1 at 1-year liver biopsy), time to METAVIR F2-stage fibrosis, and fibrosis rate (calculated using liver biopsies graded by METAVIR scoring F0-4; fibrosis rate = fibrosis stage/year post transplant). RF was defined as ≥ 0.5 units/year.

RESULTS

Multivariate analysis revealed that donor age and peak HCV viral load were significant risks for RF, when fibrosis rate was used to define RF. Advanced donor age was a risk for rapid progression to F2-stage fibrosis, whereas genotype 2 or 3 HCV infection was protective. Fibrosis rate had the strongest correlation with time to cirrhosis development (P < 0.0001, r = -0.76) and was the most accurate predictor of rapid graft cirrhosis (P < 0.0001, area under the curve 0.979, sensitivity 100%, specificity 94%).

CONCLUSION

Different measures of RF progression identify different risks for RF and are not directly comparable. Fibrosis rate was the most accurate predictor of rapid graft cirrhosis.

MicroRNAs in Liver Disease: Bench to Bedside

MicroRNAs (miRs) are small non-coding RNAs that negatively regulate gene expression by pairing with partially complementary target sequences in the 3'UTRs of mRNAs to promote degradation and/or block translation. Aberrant miR expression is associated with development of multiple diseases including hepatic diseases. The role of miRs in the regulation of gene expression and rapid progress in the field of microRNA research are resulting in momentum toward development of diagnostic markers and novel therapeutic strategies for human liver diseases. Recent studies provide clear evidence that miRs are abundant in the liver and modulate a diverse spectrum of biological functions, thereby supporting an association between alterations of miR homeostasis and pathological liver diseases. Here we review the role of miRs in liver as their physiological and pathological importance has been demonstrated in metabolism, immunity, viral hepatitis, oncogenesis, fatty liver diseases (alcoholic and non-alcoholic), drug-induced liver injury, fibrosis as well as acute liver failure.

Digital image analysis of collagen assessment of progression of fibrosis in recurrent HCV after liver transplantation

BACKGROUND & AIMS

Histological assessment of fibrosis progression is currently performed by staging systems which are not continuous quantitative measurements. We aimed at assessing a quantitative measurement of fibrosis collagen proportionate area (CPA), to evaluate fibrosis progression and compare it to Ishak stage progression.

METHODS

We studied a consecutive cohort of 155 patients with recurrent HCV hepatitis after liver transplantation (LT), who had liver biopsies at one year and were subsequently evaluated for progression of fibrosis using CPA and Ishak staging, and correlated with clinical decompensation. The upper quartile of distribution of fibrosis rates (difference in CPA or Ishak stage between paired biopsies) defined fast fibrosers.

RESULTS

Patients had 610 biopsies and a median follow-up of 116 (18-252) months. Decompensation occurred in 29 (18%) patients. Median Ishak stage progression rate was 0.42 units/year: (24 (15%) fast fibrosers). Median CPA fibrosis progression rate was 0.71%/year (36 (23%) fast fibrosers). Clinical decompensation was independently associated by Cox regression only with CPA (p=0.007), with AUROCs of 0.81 (95% CI 0.71-0.91) compared to 0.68 (95% CI 0.56-0.81) for Ishak stage. Fast fibrosis defined by CPA progression was independently associated with histological de novo hepatitis (OR: 3.77), older donor age (OR: 1.03) and non-use/discontinuation of azathioprine before 1 year post-LT (OR: 3.85), whereas when defined by Ishak progression, fast fibrosers was only associated with histological de novo hepatitis.

CONCLUSIONS

CPA fibrosis progression rate is a better predictor of clinical outcome than progression by Ishak stage. Histological de novo hepatitis, older donor age and non-use/discontinuation of azathioprine are associated with rapid fibrosis progression in recurrent HCV chronic hepatitis after liver transplantation.

Management of recurrent hepatitis C in orthotopic liver transplant recipients

End-stage liver disease and hepatocellular carcinoma from chronic hepatitis C are the most common indications for orthotopic liver transplantation and the incidence of both are projected to increase over the next decade. Recurrent hepatitis C virus infection of the allograft is associated with an accelerated progression to cirrhosis, graft loss, and death. This article presents an overview of the natural history of hepatitis C virus recurrence in liver transplant recipients and guidance on optimal management strategies.

MicroRNA signature at the time of clinical HCV recurrence associates with aggressive fibrosis progression post-liver transplantation

Diagnosis and prediction of the severity of hepatitis C virus recurrence (HCVrec) after liver transplantation (LT) remain a challenge. MicroRNAs have been recently recognized as potential disease biomarkers. Archival liver biopsy samples from 43 HCV+ LT recipients were collected at clinical HCVrec time and at 3 years post-LT. Patients were classified as progressors (P = F0/F1) or nonprogressors (NP = F3/F4) according to the severity of fibrosis on the 3-year biopsy. Training (n = 27) and validation (n = 16) sets were defined. RNA was isolated from all biopsies at clinical HCVrec time, labeled and hybridized to miRNA-arrays. Progressors versus nonprogressors were compared using the two-sample t-test. A p-value ≤0.01 was considered significant. The ingenuity pathway analysis tool was used for microRNA and miRNA:mRNA ontology data integration. Nine microRNAs were differentially expressed between groups. A supervised cluster analysis separated samples in two well-defined groups (progressors vs. nonprogressors). Pathway analysis associated those microRNAs with hepatitis, steatosis, fibrosis, cirrhosis and T cell-related immune response. Data integration identified 17 genes from a previous genomic study as 9-microRNAs signature targets. Seven microRNAs were successfully validated in the validation set using QPCR. We have identified a 9-microRNA signature able to identify early post-LT patients at high risk of severe HCVrec during long-term follow-up.

Living-donor liver transplantation and hepatitis C

Hepatitis-C-virus- (HCV-) related end-stage cirrhosis is the primary indication for liver transplantation in many countries. Unfortunately, however, HCV is not eliminated by transplantation and graft reinfection is universal, resulting in fibrosis, cirrhosis, and finally graft decompression. In areas with low deceased-donor organ availability like Japan, living-donor liver transplantation (LDLT) is similarly indicated for HCV cirrhosis as deceased-donor liver transplantation (DDLT) in Western countries and accepted as an established treatment for HCV-cirrhosis, and the results are equivalent to those of DDLT. To prevent graft failure due to recurrent hepatitis C, antiviral treatment with pegylated-interferon and ribavirin is currently considered the most promising regimen with a sustained viral response rate of around 30% to 35%, although the survival benefit of this regimen remains to be investigated. In contrast to DDLT, many Japanese LDLT centers have reported modified treatment regimens as best efforts to secure first graft, such as aggressive preemptive antiviral treatment, escalation of dosages, and elongation of treatment duration.

Long-term antiviral treatment for recurrent hepatitis C after liver transplantation

BACKGROUND AND AIMS

The management of patients treated for hepatitis C recurrence after liver transplantation and not achieving virological response following treatment with interferon plus ribavirin is controversial.

METHODS

A retrospective analysis of the outcomes of 70 patients non-responders to antiviral treatment after liver transplantation was performed. Twenty-one patients (30.0%; Group A) were treated for ≤ 12 months and 49 (70.0%; Group B) for more than 12 months.

RESULTS

The 2 groups were comparable for main demographic, clinical and pathological variables. Median duration of antiviral treatment was 8.2 months in Group A and 33.4 months in Group B. No patient achieved a complete virological response. The 5-year patient hepatitis C-related survival rate was 49.2% in Group A and 88.3% in Group B (P=0.002), while the 5-year graft survival rate was 49.2% in Group A and 85.9% in Group B (P=0.007). The median yearly fibrosis progression rate was 1.21 per year in Group A and 0.40 per year in Group B (P=0.001).

CONCLUSIONS

Prolonged antiviral treatment showed an overall beneficial effect in transplanted patients with a recurrent hepatitis C infection and not responding to conventional therapy. The treatment should be continued as long as it is permitted, in order to improve clinical and histological outcomes.

Elderly recipients of hepatitis C positive renal allografts can quickly develop liver disease

Our institution explored using allografts from donors with Hepatitis C virus (HCV) for elderly renal transplantation (RT). Thirteen HCV- elderly recipients were transplanted with HCV+ allografts (eD+/R-) between January 2003 and April 2009. Ninety HCV- elderly recipients of HCV- allografts (eD-/R-), eight HCV+ recipients of HCV+ allografts (D+/R+) and thirteen HCV+ recipients of HCV- allografts (D-/R+) were also transplanted. Median follow-up was 1.5 (range 0.8-5) years. Seven eD+/R- developed a positive HCV viral load and six had elevated liver transaminases with evidence of hepatitis on biopsy. Overall, eD+/R- survival was 46% while the eD-/R- survival was 85% (P = 0.003). Seven eD+/R- died during follow-up. Causes included multi-organ failure and sepsis (n = 4), cancer (n = 1), failure-to-thrive (n = 1) and surgical complications (n = 1). One eD+/R- died from causes directly related to HCV infection. In conclusion, multiple eD+/R- quickly developed HCV-related liver disease and infections were a frequent cause of morbidity and mortality.

Impact of donor histology on survival following liver transplantation for chronic hepatitis C virus infection: a Scandinavian single-center experience

OBJECTIVE

Survival following liver transplantation for hepatitis C virus (HCV) infection is affected by several factors. The aims of this single-center study were to evaluate survival from 1992 to 2006 in HCV-infected liver transplant recipients and to identify factors influencing patient and graft survival, with particular focus on donor liver histopathology.

MATERIAL AND METHODS

Survival among 84 patients transplanted for HCV-related liver disease at the Sahlgrenska University Hospital during the above period was evaluated. Median follow-up time was 57 months (range 28-87). A perioperative liver biopsy from the donor liver graft was available in 68 cases. Biopsies were assessed for fibrosis, necroinflammatory activity, and degree of steatosis. Patient and graft survival according to relevant factors including donor histopathology were analyzed by Kaplan-Meier analysis.

RESULTS

We found an association between donor liver fibrosis and patient survival (p = 0.016) as well as between graft survival and portal inflammation in the donor liver (p = 0.026). Both these associations remained significant in multivariate analysis (p = 0.007 and 0.017 respectively). Moreover, recipient age over 60 was found predictive of patient survival and repeated steroid boluses or steroid-resistant rejection of graft survival. Donor age was high throughout the study period.

CONCLUSION

Histopathological features, especially portal inflammation and stage of fibrosis, in the donor liver may deleteriously affect graft and patient survival following HCV-related liver transplantation. Thus, pretransplant evaluation of donor histopathology may be of value in the selection of donors for transplantation of HCV-positive individuals, especially among donors older than 60 years.

Liver transplantation and hepatitis C

Hepatitis-C-virus- (HCV-) related end-stage cirrhosis is the primary indication for liver transplantation in many countries. Unfortunately, however, HCV is not eliminated by transplantation and graft reinfection is universal, resulting in fibrosis, cirrhosis, and finally graft decompensation. The use of poor quality organs, particularly from older donors, has a highly negative impact on the severity of recurrence and patient/graft survival. Although immunosuppressive regimens have a considerable impact on the outcome, the optimal regimen after liver transplantation for HCV-infected patients remains unclear. Disease progression monitoring with protocol biopsy and new noninvasive methods is essential for predicting patient/graft outcome and starting antiviral treatment with the appropriate timing. Antiviral treatment with pegylated interferon and ribavirin is currently considered the most promising regimen with a sustained viral response rate of around 30% to 35%, although the survival benefit of this regimen remains to be investigated. Living-donor liver transplantation is now widely accepted as an established treatment for HCV cirrhosis and the results are equivalent to those of deceased donor liver transplantation.

Early activation of interferon-stimulated genes in human liver allografts: relationship with acute rejection and histological outcome

BACKGROUND

Innate immunity mechanisms have been shown to play a paramount role in organ transplantation. Our aim was to investigate the hypothesis that activation of the interferon system may affect clinically relevant outcomes, such as acute rejection and/or early fibrosis progression, after liver transplantation.

METHODS

We studied 71 consecutive recipients (57 males; 25 with hepatitis C) who underwent two per protocol graft biopsies: the first, within 60 days after the transplant operation (median 24) and the second, after 1 year. The mRNA expression for five interferon-stimulated genes (Mx1, OAS2, PKR, IRF7A, IFI16) was measured on the first biopsy specimens. The main outcome measures were acute rejection during the first post-transplant year and fibrosis progression at the second biopsy.

RESULTS

On multivariate analysis, the independent predictors of gene expression were hepatitis C (Mx1, OAS2, PKR and IFI16), donor age (IFI16) and recipient gender (IRF7A) (P < .05 for all). During the first post-transplant year, 19/71 patients (27%) had acute cellular rejection. At multivariate analysis, acute cellular rejection was independently predicted by high IRF7A mRNA expression. At the end of follow-up, 25 patients had some degree of fibrosis (F2 or higher in seven cases). On multivariate analysis, hepatitis C etiology, recipient age, and OAS2 overexpression were independent predictors of early fibrosis progression.

CONCLUSIONS

In the early postoperative period of liver transplantation, interferon-stimulated gene activation is dependent on hepatitis C recurrence (the main factor responsible for early fibrosis progression) and donor age, and is related to the risk of acute cellular rejection.

Management of recurrent hepatitis C infection after liver transplantation

Recurrence of hepatitis C virus remains a near-universal phenomenon after liver transplantation (LT) and is responsible for the high morbidity and low survival seen in these patients. The severity of recurrent disease varies depending on multiple factors, only some of which are modifiable. Antiviral therapy is associated with improved outcomes, but viral clearance is only attainable in a small percentage of this patient population. This patient population is in need of new therapeutic options, and it remains to be seen whether direct-acting antiviral agents will be the answer to this ongoing therapeutic question.

Transcriptome at the time of hepatitis C virus recurrence may predict the severity of fibrosis progression after liver transplantation

Allograft gene expression analysis may provide insights into the mechanisms involved in liver damage during hepatitis C virus recurrence (HCVrec) after orthotopic liver transplantation (OLT) and allow the identification of patients who have a higher risk of developing severe disease. Forty-three OLT recipients with hepatitis C virus (HCV) were evaluated. Genomewide gene expression analysis was performed with formalin-fixed, paraffin-embedded (FFPE) liver biopsy samples obtained from 21 OLT recipients with HCV at the time of clinical HCVrec, which was defined as increased alanine aminotransferase levels and detectable HCV RNA levels in serum. Patients were classified into 3 groups according to the severity of the fibrosis in the liver biopsies at 36 months post-OLT : group 1 (G1) for mild fibrosis (F0-F1), group 2 for moderate fibrosis (F2), and group 3 (G3) for severe fibrosis (F3-F4). No significant differences were observed between the groups with respect to donor age, histology during HCVrec, treated episodes of acute cellular rejection, or immunosuppression therapy. The results were validated in the remaining 22 OLT recipients with HCV using quantitative real-time polymerase chain reaction. Fifty-seven beadtypes showed significantly different expression (P < 0.001) between the groups during HCVrec. In G3, the gene expression of interleukin-28RA (IL-28RA), IL-28, and angiotensin-converting enzyme was up-regulated. Samples from G1 and G3 were used to determine whether a multigenetic classifier could be derived to predict the group class. The final model included the intercept and 9 bead types. Pairwise scatter plots of these 9 bead types revealed that G1 and G3 were well separated with respect to each gene. Our analysis has demonstrated the utility of a set of molecular markers indicating HCVrec severity early after OLT.

Results of a two-center study comparing hepatic fibrosis progression in HCV-positive liver transplant patients receiving cyclosporine or tacrolimus

A 2-center retrospective analysis was performed in 60 patients undergoing liver transplantation for hepatitis C virus (HCV)-related disease (cyclosporine in 20, tacrolimus in 40). Mean (±SEM) follow-up was 23.6 ± 22.5 and 22.3 ± 13.7 months in patients receiving cyclosporine or tacrolimus, respectively. Clinically indicated biopsies were performed in 15/20 cyclosporine patients (75%) and 22/40 tacrolimus patients (55%; P = .17). The Ishak fibrosis score was significantly lower in cyclosporine-treated patients versus tacrolimus-treated patients (mean 1.7 ± 0.4 vs 3.1 ± 0.4; P = .023), as was percentage of fibrosis grade Ishak ≥4 (7% vs 41%; P = .028). The mean time to moderate fibrosis (Ishak score ≥3) was 38.2 ± 15.1 months in cyclosporine patients (4/15) and 23.5 ± 12.6 months in tacrolimus patients (14/22); the difference was not statistically significant (P = .09). This retrospective study suggests that cyclosporine-based immunosuppression is associated with less severe hepatic fibrosis in HCV-positive liver transplant recipients compared with tacrolimus-based regimens, but a larger prospective comparative trial is necessary to confirm these findings.